BACK INTO SPACE

By William J. Broad; William J. Broad is a science reporter for The New York Times who helps cover the space program.

Published: July 3, 1988

THE CREW TENSES AS SIRENS WAIL AND warning lights wink on. All but one of the space shuttle's three main engines have mysteriously failed minutes after takeoff, leaving the ship crippled dozens of miles above the choppy Atlantic. Previously, the only option would have been a potentially deadly controlled crash in the water. But now quick steps are taken. The commander and pilot jettison the huge external fuel tank and stabilize the spaceship as it plummets. Five miles up, a crew member explosively blows off the shuttle's side hatch and extends a telescoping escape pole 12 feet beyond the ship. With the craft on autopilot, the astronauts gather on the shuttle's middeck, still dressed, as they were at takeoff, in newly designed flight suits with built-in parachutes, life rafts and oxygen supplies, so they can survive the rarefied atmosphere high above the earth. At four miles up, they bail out. One by one, they hook onto the escape pole and slide down, the device guiding them away from the craft, keeping the 200-mile-per-hour headwinds from bashing them into a wing or engine pod as they fall from the doomed ship. Soon they are floating in their parachutes to a safe landing in the ocean.

SHOULD THE SPACE SHUTTLE DISCOVERY encounter such an emergency on her four-day flight, scheduled to blast off from Cape Canaveral in late August or early September, the last man out would be Capt. Frederick H. Hauck of the Navy. His position as commander of the first post-Challenger flight is probably the single point of greatest responsibility in the revival of the nation's manned space program. The Discovery mission will attempt not only to deploy a giant communications satellite but, more important, to reassert America's manned presence in space.

Hauck is intimately familiar with duty and close calls. A third-generation Navy man (and father of a son who is now in the Navy as well), he flew 114 combat sorties in Southeast Asia and once bailed out of a burning jet seconds before it crashed in the water.

''It was interesting,'' he recalled during an interview at the Johnson Space Center in Houston. A smile played on his face, and he seemed actually to relish the memory. ''It was a milky white day. No horizon. I heard a thump and noticed I had lost my left engine. The airplane suddenly pitched down, water coming up at me. In that split second I thought, 'I'm going to die.' And then I thought, 'Hey, I don't have to. I can eject.' ''

Like the rest of the five-man Discovery crew, now undergoing training of unprecedented intensity, Hauck is seasoned and cool, ready to move beyond the legacy of the Challenger explosion, history's worst space disaster. All are shuttle veterans. All are men. Four of the five have military backgrounds, mainly as fighter and test pilots, and are inured to the possibility of one day never returning from a mission. In addition to Commander Hauck, the crew includes the pilot, Col. Richard O. Covey, formerly an Air Force fighter and test pilot, and three mission specialists: George D. (Pinky) Nelson, an astronomer; John M. Lounge, a former Navy aviator, and Lieut. Col. David C. Hilmers of the Marine Corps, a former attack pilot.

The differences between these astronauts and their predecessors on the ill-fated Challenger could hardly be more striking - or more purposeful. The seven Challenger astronauts, climbing aboard their winged spaceship that bitterly cold morning in January 1986, seemed to epitomize the warmth and diversity of the American dream. One was black. One was Asian-American. Two were women. Three were space rookies, eager to frolic on the high frontier and talk about mankind's destiny in space. Christa McAuliffe, a high-school teacher, hoped to share what she called ''the ultimate field trip'' with the nation's children. Ronald E. McNair would have taken along his saxophone, if the space agency had let him.

These five men, by contrast, are singleminded professionals, laconic, macho - the right stuff, if ever there was such a breed. Whatever they lack in diversity is made up in technical skill. The first shuttle team to be composed entirely of veteran astronauts, they have flown more missions, practiced longer on the ground and weathered more mock accidents in flight simulators than any other Americans who have dared to blast into space. In short, they are the most experienced crew to train for orbit since the start of the American space program more than a quarter century ago.

But they are not just a refinement of the old fighter-jock astronaut. Those early space explorers, though tough, were largely passive participants in the vast machinery of taming the heavens. In contrast, this crew represents a new class of astronaut activist, working closely with engineers to reshape the nation's space program, to insure that their overhauled spaceship is as safe as possible.

Although they can smile engagingly and jest with one another, these men have been schooled to set aside their emotions and downplay public curiosity about the risk and danger of their jobs. They are affable introverts. Most especially, they belittle any hint that bravery was a factor in accepting what will surely be one of the most unnerving jobs in the history of space flight.